Porthleven is developing a reputation as a bit of a foodie's place, with some great restaurants (incl Kota, Kota Kai, Amelie). Nauti Pizza and the harbour is popular with families. Unfortunately you just missed the food festival!
It's brilliantly positioned for walking; at low tide you can walk the beach out to Loe Bar and Penrose Hill, and all the way down that coast you have Gunwalloe, Mullion Cove and the Lizard in one direction, or Rinsey Cove, Praa Sands, Prussia Cove, Perranuthnoe and Marazion if you head north and west.
Both the Ship and The Harbour are decent pubs actually in Porthleven, oh and Ann's Pasties on Fore Street are great.
Enjoy!